In short
- 401 ADU permits since 2018.
- 163 in 2025, up 24% from 2024.
About this data
- Source: California HCD Housing Element Annual Progress Reports. The state data does not say whether an ADU is detached, attached, a garage conversion or a JADU, so most records show as 'unknown'. Permit valuations are not published in this source. Timelines use the application date the city reported to the state, matched to the permit where possible; some cities report their planning application date, so timelines can include planning review. Each project is counted once, in its building-permit year (or completion year when no permit date was reported).
- Ventura reported no ADU building-permit dates for 2023; that year's bar counts completions only and is likely incomplete.
Permits by year
Permits by year and type (table)
| Year | All ADU permits | Garage conversions | Detached |
|---|---|---|---|
| 2018 | 1 | — | — |
| 2019 | 12 | — | — |
| 2020 | 11 | — | — |
| 2021 | 1 | — | — |
| 2022 | 47 | — | — |
| 2023 (incomplete report) | 35 | — | — |
| 2024 | 131 | — | — |
| 2025 | 163 | — | — |
“—” means the source for that year does not report ADU type.
Read more: ADU types explained
Not counted above: 1 approved projects with no building permit reported yet.
ADU rules in Ventura
State law check: No HCD review letter on file (that isn't a finding either way). Its junior-ADU owner rule is stricter than current state law.
| Rule | Ventura's code | State law guarantees |
|---|---|---|
| Maximum size | 850 sq ft (studio or 1 bedroom) or 1,200 sq ft (2+ bedrooms); attached 50% of the house, at least 800. Junior ADU 500 sq ft. | At least 850 sq ft (1,000 sq ft with 2+ bedrooms) must be allowed; an 800 sq ft detached ADU always is. Conversions of existing space have no size cap. Junior ADU: up to 500 sq ft. |
| Height | Detached: 18 ft, plus 2 ft for roof pitch. Attached: 25 ft, 2 stories. | Detached: at least 16 ft (18 ft within ½ mile of transit, plus 2 ft for a matching roof). Attached: 25 ft or the zone's limit, whichever is lower. |
| Setbacks | 4 ft side and rear; the zone's front setback. | No more than 4 ft side and rear; none for conversions of existing space. |
| Parking | None, except 1 space in the city's ADU Mandatory Parking Area. | At most 1 space; none within ½ mile of transit and in several other cases. No replacement parking when a garage is converted. |
| Owner living on site | None for ADUs created since 2020. Junior ADU: required. | None for ADUs. A junior ADU that shares a bathroom with the house requires the owner to live in one of them. |
| How many on a single-family lot | One converted ADU, one junior ADU and one detached ADU. | One ADU converted from existing space, one junior ADU and one new detached ADU (up to 800 sq ft). From January 1, 2027: two new detached ADUs (a city then needn't allow a junior ADU on that lot). |
| Short-term rentals | Not for less than 30 days. | No guarantee: cities may require rentals of more than 30 days, and junior ADUs can't be short-term rentals. |
- No new ADUs in Very High Fire Hazard Severity Zones (junior ADUs and state-law ADUs excepted).
- Coastal Zone lots need a coastal exemption or permit.
Where local rules conflict with state law, state law controls. Sources: San Buenaventura Municipal Code Ch. 24.430 (Ord. 2024-012, Jan 14, 2025); HCD's list of review letters; California ADU rules. Verified Sep 29, 2026. Rules change and every lot is different: confirm with the city before you design.
How long permits take
| Type | Median days, application to permit | Middle half | Permits |
|---|---|---|---|
| Unclassified | too few to say | 2 |
Middle half: the range covering the middle 50% of permits (a quarter were lower, a quarter higher).
Read more: ADU permit times across Ventura County · How long ADUs take to build
What neighbors declared as cost
Cost data (declared permit valuations) is not published for this area in these sources.
Read more: How to choose an ADU builder
An ADU builder serving Ventura? Feature your business on this page.
Questions about ADUs in Ventura
How many ADUs have been permitted in Ventura?
Public records show 401 ADU permits in Ventura from 2018 through 2025. 163 in 2025, up 24% from 2024. These counts come from the city's reports to the state, which place a project in its completion year when no permit date was reported.
Can I build an ADU on my property in Ventura?
California law allows ADUs on most lots with a house, including in Ventura, but what you can build depends on your lot, local rules and utilities. This site shows permits, not eligibility. See California ADU rules.
Where do I apply for an ADU permit in Ventura?
Apply with the City of Ventura's Planning and Building and Safety divisions, which offer free pre-approved detached ADU plans. Official ADU page.
How current is this?
- State annual progress reports: through 2025 (published once a year)
How our data works · Download the data · Free to reuse with credit to SoCal ADU Tracker (socaladutracker.com), under CC BY 4.0.